...Eligible mutations are summarized in Appendix I. Eligible patients will be assigned to one of the 4 following cohorts:Cohort 1: NSCLC with EGFR or HER2 exon 20 insertion mutationCohort 2: Breast cancer with an allosteric HER2 mutation and EGFR/HER2 exon 20 insertion mutationsCohort 3: Any tumor (except breast) with an S310F/Y mutationCohort 4: Any other allosteric HER2 mutation and EGFR/HER2 exon 20 insertion mutations not assigned to Cohorts 1-3;Adequate archival tumor tissue or willing to undergo pretreatment biopsy;Measurable disease according to RECIST version 1.1....